org.apache.commons.vfs2.provider

Class AbstractFileSystem

java.lang.Object

org.apache.commons.vfs2.provider.AbstractVfsComponent

org.apache.commons.vfs2.provider.AbstractFileSystem

All Implemented Interfaces:

Closeable, AutoCloseable, FileSystem, VfsComponent

Direct Known Subclasses:

CompressedFileFileSystem, FtpFileSystem, HdfsFileSystem, Http4FileSystem, Http5FileSystem, HttpFileSystem, LocalFileSystem, RamFileSystem, SftpFileSystem, TarFileSystem, UrlFileSystem, VirtualFileSystem, ZipFileSystem

public abstract class AbstractFileSystem
extends AbstractVfsComponent
implements FileSystem

A partial FileSystem implementation.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractFileSystem(FileName rootFileName, FileObject parentLayer, FileSystemOptions fileSystemOptions)

Method Summary

Modifier and Type	Method and Description
protected abstract void	addCapabilities(Collection<Capability> caps) Adds the capabilities of this file system.
void	addJunction(String junctionPoint, FileObject targetFile) Adds a junction to this file system.
void	addListener(FileObject file, FileListener listener) Adds a listener on a file in this file system.
void	close() Closes this component.
void	closeCommunicationLink() Closes the underlying link used to access the files.
protected abstract FileObject	createFile(AbstractFileName name) Creates a file object.
protected FileObject	decorateFileObject(FileObject file)
protected void	doCloseCommunicationLink() Closes the underlying link used to access the files.
protected File	doReplicateFile(FileObject file, FileSelector selector) Creates a temporary local copy of a file and its descendants.
void	fireFileChanged(FileObject file) Fires a file changed event.
void	fireFileCreated(FileObject file) Fires a file create event.
void	fireFileDeleted(FileObject file) Fires a file delete event.
Object	getAttribute(String attrName) Retrieves the attribute with the specified name.
protected FileObject	getFileFromCache(FileName name) Returns a cached file.
FileSystemManager	getFileSystemManager() Returns the FileSystemManager used to instantiate this file system.
FileSystemOptions	getFileSystemOptions() Returns the FileSystemOptions used to instantiate this file system.
double	getLastModTimeAccuracy() Returns the accuracy of the last modification time.
FileObject	getParentLayer() Returns the parent layer if this is a layered file system.
FileObject	getRoot() Returns the root file of this file system.
FileName	getRootName() Returns the name of the root of this file system.
String	getRootURI() Returns the root URI specified for this file System.
boolean	hasCapability(Capability capability) Determines if this file system has a particular capability.
void	init() Initializes this component.
boolean	isOpen() Checks if this file system has open streams.
boolean	isReleaseable() Returns true if no file is using this FileSystem.
protected void	notifyAllStreamsClosed() Called after all file-objects closed their streams.
protected void	putFileToCache(FileObject file) Adds a file object to the cache.
protected void	removeFileFromCache(FileName name) Removes a cached file.
void	removeJunction(String junctionPoint) Removes a junction from this file system.
void	removeListener(FileObject file, FileListener listener) Removes a listener from a file in this file system.
File	replicateFile(FileObject file, FileSelector selector) Creates a temporary local copy of a file and its descendants.
FileObject	resolveFile(FileName name) Finds a file in this file system.
FileObject	resolveFile(String nameStr) Finds a file in this file system.
void	setAttribute(String attrName, Object value) Sets the attribute with the specified name.

Methods inherited from class org.apache.commons.vfs2.provider.AbstractVfsComponent

getContext, getLogger, setContext, setLogger

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractFileSystem

protected AbstractFileSystem(FileName rootFileName,
                             FileObject parentLayer,
                             FileSystemOptions fileSystemOptions)

Method Detail

init

public void init()
          throws FileSystemException

Initializes this component.

Specified by:

init in interface VfsComponent

Overrides:

init in class AbstractVfsComponent

Throws:

FileSystemException - if an error occurs.

close

public void close()

Closes this component.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in interface VfsComponent

Overrides:

close in class AbstractVfsComponent

closeCommunicationLink

public void closeCommunicationLink()

Closes the underlying link used to access the files.

doCloseCommunicationLink

protected void doCloseCommunicationLink()

Closes the underlying link used to access the files.

createFile

protected abstract FileObject createFile(AbstractFileName name)
                                  throws Exception

Creates a file object.

This method is called only if the requested file is not cached.

Parameters:

name - name referencing the new file.

Returns:

new created FileObject.

Throws:

Exception - might throw an Exception, which is then wrapped in FileSystemException.

addCapabilities

protected abstract void addCapabilities(Collection<Capability> caps)

Adds the capabilities of this file system.

Parameters:

caps - collections of Capabilities, can be immutable.

getRootName

public FileName getRootName()

Returns the name of the root of this file system.

Specified by:

getRootName in interface FileSystem

Returns:

the root FileName.

getRootURI

public String getRootURI()

Returns the root URI specified for this file System.

Specified by:

getRootURI in interface FileSystem

Returns:

The root URI used in this file system.

Since:

2.0

putFileToCache

protected void putFileToCache(FileObject file)

Adds a file object to the cache.

Parameters:

file - the file to add.

getFileFromCache

protected FileObject getFileFromCache(FileName name)

Returns a cached file.

Parameters:

name - name to search for.

Returns:

file object or null if not found.

removeFileFromCache

protected void removeFileFromCache(FileName name)

Removes a cached file.

Parameters:

name - The file name to remove.

hasCapability

public boolean hasCapability(Capability capability)

Determines if this file system has a particular capability.

Specified by:

hasCapability in interface FileSystem

Parameters:

capability - the Capability to check for.

Returns:

true if the FileSystem has the Capability, false otherwise.

getAttribute

public Object getAttribute(String attrName)
                    throws FileSystemException

Retrieves the attribute with the specified name. The default implementation simply throws an exception.

Specified by:

getAttribute in interface FileSystem

Parameters:

attrName - The name of the attribute.

Returns:

the Object associated with the attribute or null if no object is.

Throws:

FileSystemException - if an error occurs.

See Also:

FileContent.getAttribute(java.lang.String)

setAttribute

public void setAttribute(String attrName,
                         Object value)
                  throws FileSystemException

Sets the attribute with the specified name. The default implementation simply throws an exception.

Specified by:

setAttribute in interface FileSystem

Parameters:

attrName - the attribute name.

value - The object to associate with the attribute.

Throws:

FileSystemException - if an error occurs.

See Also:

FileContent.setAttribute(java.lang.String, java.lang.Object)

getParentLayer

public FileObject getParentLayer()
                          throws FileSystemException

Returns the parent layer if this is a layered file system.

Specified by:

getParentLayer in interface FileSystem

Returns:

The FileObject for the parent layer.

Throws:

FileSystemException - if an error occurs.

getRoot

public FileObject getRoot()
                   throws FileSystemException

Returns the root file of this file system.

Specified by:

getRoot in interface FileSystem

Returns:

The root FileObject of the FileSystem

Throws:

FileSystemException - if an error occurs.

resolveFile

public FileObject resolveFile(String nameStr)
                       throws FileSystemException

Finds a file in this file system.

Specified by:

resolveFile in interface FileSystem

Parameters:

nameStr - The name of the file to resolve.

Returns:

The located FileObject or null if none could be located.

Throws:

FileSystemException - if an error occurs.

resolveFile

public FileObject resolveFile(FileName name)
                       throws FileSystemException

Finds a file in this file system.

Specified by:

resolveFile in interface FileSystem

Parameters:

name - The name of the file to locate.

Returns:

The located FileObject or null if none could be located.

Throws:

FileSystemException - if an error occurs.

decorateFileObject

protected FileObject decorateFileObject(FileObject file)
                                 throws FileSystemException

Throws:

FileSystemException

replicateFile

public File replicateFile(FileObject file,
                          FileSelector selector)
                   throws FileSystemException

Creates a temporary local copy of a file and its descendants.

Specified by:

replicateFile in interface FileSystem

Parameters:

file - The FileObject to replicate.

selector - The FileSelector.

Returns:

The replicated File.

Throws:

FileSystemException - if an error occurs.

getFileSystemOptions

public FileSystemOptions getFileSystemOptions()

Returns the FileSystemOptions used to instantiate this file system.

Specified by:

getFileSystemOptions in interface FileSystem

Returns:

the FileSystemOptions.

getFileSystemManager

public FileSystemManager getFileSystemManager()

Returns the FileSystemManager used to instantiate this file system.

Specified by:

getFileSystemManager in interface FileSystem

Returns:

the FileSystemManager.

getLastModTimeAccuracy

public double getLastModTimeAccuracy()

Returns the accuracy of the last modification time.

Specified by:

getLastModTimeAccuracy in interface FileSystem

Returns:

ms 0 perfectly accurate, >0 might be off by this value e.g. sftp 1000ms

doReplicateFile

protected File doReplicateFile(FileObject file,
                               FileSelector selector)
                        throws Exception

Creates a temporary local copy of a file and its descendants.

Parameters:

file - the start of the tree.

selector - selection what to do with childs.

Returns:

replicated root file.

Throws:

Exception - any Exception is wrapped as FileSystemException.

addJunction

public void addJunction(String junctionPoint,
                        FileObject targetFile)
                 throws FileSystemException

Adds a junction to this file system.

Specified by:

addJunction in interface FileSystem

Parameters:

junctionPoint - The junction point.

targetFile - The target to add.

Throws:

FileSystemException - if an error occurs.

removeJunction

public void removeJunction(String junctionPoint)
                    throws FileSystemException

Removes a junction from this file system.

Specified by:

removeJunction in interface FileSystem

Parameters:

junctionPoint - The junction point.

Throws:

FileSystemException - if an error occurs

addListener

public void addListener(FileObject file,
                        FileListener listener)

Adds a listener on a file in this file system.

Specified by:

addListener in interface FileSystem

Parameters:

file - The FileObject to be monitored.

listener - The FileListener

removeListener

public void removeListener(FileObject file,
                           FileListener listener)

Removes a listener from a file in this file system.

Specified by:

removeListener in interface FileSystem

Parameters:

file - The FileObject to be monitored.

listener - The FileListener

fireFileCreated

public void fireFileCreated(FileObject file)

Fires a file create event.

Parameters:

file - The FileObject that was created.

fireFileDeleted

public void fireFileDeleted(FileObject file)

Fires a file delete event.

Parameters:

file - The FileObject that was deleted.

fireFileChanged

public void fireFileChanged(FileObject file)

Fires a file changed event.

This will only happen if you monitor the file using FileMonitor.

Parameters:

file - The FileObject that changed.

isReleaseable

public boolean isReleaseable()

Returns true if no file is using this FileSystem.

Returns:

true if no file is using this FileSystem.

notifyAllStreamsClosed

protected void notifyAllStreamsClosed()

Called after all file-objects closed their streams.

isOpen

public boolean isOpen()

Checks if this file system has open streams.

Returns:

true if the FileSystem has open streams.